Spurs looking to tighten up leaky defense

Influenced as it was by key injuries, the Spurs’ late-season slide deserves something of an asterisk. But this much is clear: They’re limping, rather than sprinting, into the postseason, which begins Sunday with Game 1 of their first-round series against the Lakers.

The Spurs suffered breakdowns and regressions in numerous areas during that stretch. None was more noticeable than on the defensive end.

“We’re better than we were last year,” head coach Gregg Popovich said, “but not where we wanted to be.”

They had been on track to improve significantly, fulfilling Popovich’s preseason challenge to restore their defense to elite status after ranking 10th in points allowed per 100 possessions last season. That was good, but not good enough as the Spurs imploded against Oklahoma City in the Western Conference Finals.

They climbed to third this season, their best finish since 2007-08.

But that tells only part of the story. Dominant through 61 games, the Spurs slipped significantly over the final 21 — particularly at the 3-point line, where injuries to Tony Parker and Manu Ginobili deprived them of their most experienced and, believe it or not, effective perimeter defenders.

Interestingly, the Spurs’ interior defense remained virtually unchanged, ranking among the top 10 in opposing points in the paint during both spans while maintaining below-average percentages within eight feet of the rim. That only underscores their recent dropoff at the arc, one that could sabotage their season if it remains unchecked.

“We didn’t end the year well defensively,” Tim Duncan said. “With more focus time and our game plan and the playoffs set, we’ll see where we are.”

Ginobili said the quality of San Antonio’s opponents contributed to the slide.

But that doesn’t quite ring true when you consider the Timberwolves, the league’s worst 3-point shooting team, lit the Spurs up for 24 total makes in two meetings. Nor was it interior strength, but a string of five 3s in four minutes that broke open the most recent clash with the 19th-ranked, Kobe-less Lakers.

More hurtful were injuries to him and, especially, Parker.

It’s a huge mistake to view defense in a vacuum, simply as a collection of five independent duels.

Granted, these are of vital importance. Witness Bryant’s evisceration of Antonio Daniels in the 2001 Western Conference Finals, a mismatch of such epic proportions that the Spurs immediately signed Bruce Bowen to deal with him.

But even more critical in this era of unmatched sophistication and preparation is collective performance, which can only be maintained with all five defenders being in the right place, at the right time, all the time. Particularly on a disciplined, scheme-oriented team like the Spurs.

“We’re not exactly a simple system,” Duncan said.

This is done through subtle and thoroughly unspectacular responsibilities like helping teammates, contesting shots, rotating correctly to open shooters. These are areas Parker (12 years of NBA experience) and Ginobili (11) excel, and this is what the Spurs have missed in their absence.

In contrast, the Spurs are only minus 1.3 percent without Kawhi Leonard and show no difference at all without Danny Green. The rest of their perimeter corps — Gary Neal, plus 1.4 percent; Cory Joseph, plus 3.0; Nando De Colo, plus 3.1; Patty Mills, plus 3.3 — all have a negative impact.

Parker’s value as a team defender is further reflected in the lineup data. He teamed with Green, Leonard, Duncan and Tiago Splitter to allow 87.7 points per 100 possessions, the fewest among 33 units that played at least 300 minutes in the NBA this season.

He and Ginobili are back now, and it couldn’t come soon enough for the Spurs as they attempt to recapture their midseason form.